Cattle guards, generally speaking, have been used for many years with cattle enclosures to allow driving of a vehicle in and out of the enclosure while preventing cattle from escaping. However, Applicant is unaware of any cattle guard which includes all of the various aspects and features of the present invention.
The following prior art is known to Applicant:
U.S. Pat. No. 1,509,739 to McLean discloses a cattle guard including a base made up of cement walls 11. The grill portion of the McLean device is bolted to the base. This is different from the teachings of the present invention wherein the base is not made of concrete and the grills may be readily removed therefrom for cleaning purposes.
U.S. Pat. No. 1,688,238 to Kamas discloses a stock barrier device which includes a plurality of supports on which parallel bars 3 rest. Kamas fails to teach a separate base and removable grills such as is disclosed herein.
U.S. Pat. No. 2,591,220 to Welter discloses a cattle guard including a base made up of a plurality of wooden timbers on which a grill structure is bolted. The side wings 36 are also bolted to the base including the timbers. This is different from the teachings of the present invention which contemplates a metallic base and grills which are readily removable therefrom.
U.S. Pat. No. 2,592,225 to Winkler discloses a portable cattle guard including a base set in concrete footings with the base and grill structure being easily removable therefrom. This is different from the teachings of the present invention which contemplates a permanent base with wings attached thereto and wherein the grills are removable for easy cleaning.
U.S. Pat. No. 2,618,469 to Mayer discloses a cattle guard having a base having a pair of end pieces and a grill which rests thereon. The present invention differs from the teachings of this patent as having different structure for the grill sub-assembly as well as different structural features for the base.
U.S. Pat. No. 3,790,135 to Christianson discloses a cattle guard having a base made up of a plurality of timbers and pipe-like sill members on which an additional layer of sill members 12 are disposed which have grill structure thereon. The present invention differs from the teachings of Christianson as disclosing a base made up of angle irons and I-beams on which a grill is removably placed.
U.S. Pat. No. 4,655,435 to Joseph, Jr. et al. discloses a cattle guard having a complicated base structure including cross pieces with cutouts therein to allow water flow therethrough. The side wings of the Joseph, Jr. et al. device are attached to the grill. The present invention differs from the teachings of this patent as attaching the side wings to the base and as including different structure in the base not requiring the cross pieces 30 which are disclosed by Joseph, Jr. et al.
Additionally, Australian patent specification 156,385 to Andrews et al. and Swiss Patent 407,642 to Blondel are known to Applicant. The Andrews et al. device has a base made up of a plurality of timbers. The present invention has a base having a different configuration. The Blondel device has a base made up of a plurality of I-beams but no side wings. As such, the present invention is believed to distinguish from these documents.
Over and above the above comments concerning the prior art known to Applicant, the present invention is patentably distinct from each of these references as including, in the base thereof, angled extensions which are provided to aid in funneling water which may flow through the base while reducing erosion of the surrounding earth.